Births in wild black and gold howler monkeys in northern Argentina

SILVANA PEKER; MARTIN KOWALEWSKI; ROMINA PAVE; LUCIANA OKLANDER; GABRIEL ZUNINO

Belo Horizonte, Brasil.

Congreso; XII Congresso Brasileiro de Primatologia; 2007

Sociedad Brasilera de Primatología

Previous studies on births in non-human primates indicated that births are expected to occur at night and at a considerable height above ground to avoid diurnal terrestrial predators. During the study we have registered 2 births at daylight (sunset) and 4 during the night. We report two live births in two groups of wild Alouatta caraya inhabiting two different kinds of forests: continuous forest (CF) and fragmented forest (FF) located 40 km from each other. The first birth took place in a group of 4 individuals (1 male, 2 adult females and 1 juvenile male) living in the CF (27° 20´ S-58° 40´ W). The second birth was observed in a group of 3 individuals (1 male, 1 adult female and a 1 juvenile male) living the FF (27°30?S and 58°41?W). Both births occurred in daylight. Both females were multiparous. Prepartum behaviors included squatting and anogenital self-examination. During the birth, the first female was situated approximately 17 m from the rest of her group on a Cecropia pachystachya branch 4 m above ground. The second female was situated 6 m from the adult male on a Ficus monckii branch 9 m above ground. Both mothers took a squatting posture during parturition and assisted the delivery with her hands. Both mothers completely ingested the placenta. Inspection of the infant by other members of the group took place the day after parturition. The first female had a permissive behavior whereas the second female did not. The distance from the ground and the occurrence of births both during day and night suggests that predator avoidance was not critical in the timing of births.